You have the boards so just need some good quality outdoor paint, or if small signs you can use Patio Paint in craft sections at WalMart, Michael's or Joanne's or other craft shops& brushes either flat artist brushes or I guess foam brush or regular paintbrush depends on how wide you want the letters.If you have never painted letters do a couple of practice pieces.I sometimes use an old flannel back tablecloth as easy to wipe off spills & protects whatever is underneath. Usually works best to have board flat & then put it on pole or whatever after it is dry. Think most are done free-hand but if you are terrible at lettering you can buy stencils at the same craft places I mentioned. When finished if you give it a couple of clear spray coats of Krylon it will help keep them nice longer., at least that is how I do it. If your question is what to put on the signs, well that's different, I typed in "garden sayings" I think it was & came up with lots & lots "Garden of Weeding""Turtle Crossing" "Butterflies Welcome" etc. So lots of sayings to pick from. If you can do art work add butterflies, birds, flowers etc. Jan

I have also read that if you trace onto the wood you should lightly go over your lines (before painting) with a small nail to make a slight groove in the wood to keep the paint "inside" the lines. Good luck with your project.

If you're on pinterest, search for garden signs, and you'll find tons of examples - and many will lead you to sites with directions on how they were made. I've made a few, and it's so much fun! If you get tired of one, you can paint over and have something new :-)